Imaging Vertical Earthquake Cycle Crustal Deformation of the San Andreas Fault System Utilizing the GAGE Facility

加利福尼亚州南部圣安德烈亚斯断层系统沿线的大地震威胁着数百万人以及数十亿美元的财产和基础设施，这使得了解地震的物理学对于满足改善地震危险估计的关键社会需求至关重要。该项目使用GAGE(Geodesy Advance Geosciences And EarthScope)设施和EarthScope提供的最先进的大地测量数据，以了解地壳如何随着板块构造和其他过程而变形。该项目特别侧重于了解垂直运动，这可能与地下水开采和积雪负荷以及地壳流体的迁移、提取和注入有关，此外还有断层作用和地震过程。在这些数据中检测异常垂直运动不仅将提高地震周期应变率估计的质量，而且也是气候、水文、海洋和地震工程界的宝贵资源。该团队正专注于利用跨越太平洋-北美板块边界的Gage设施(全球定位系统和InSAR)和沿海验潮仪数据来研究垂直形变。该项目正在利用综合的高精度GPS点测量、高空间分辨率InSAR测量和长周期验潮仪垂直时间序列观测，开发约束良好的三维地震周期形变时间序列模型产品。该研究项目有四个主要目标：(1)建立SAFS地壳垂直和水平形变的当代高分辨率GPS约束的4D模型；(2)通过GPS和InSAR的综合分析，利用这些模型改正来自新卫星的InSAR数据中的固有误差；(3)建立由GPS、InSAR和验潮仪时间序列数据得到的精细化的地壳形变4D时间序列；以及(4)探测和了解InSAR和GPS数据中常见的非构造形变。此外，该小组正在编写宣传材料，介绍如何进行InSAR观测并将其用于模拟地壳形变，并通过国家科学基金会支持的活动地球站分发这些观测数据，并正在发布软件工具，使广大地球科学界能够进行大地测量数据分析。

Major earthquakes along the San Andreas Fault system in southern California threaten millions of people and billions of dollars in property and infrastructure, which makes understanding the physics of earthquakes key in addressing a critical societal need for improved seismic hazard estimates. This project is using state-of-the-art geodetic data provided by the GAGE (Geodesy Advancing Geosciences and EarthScope) Facility and EarthScope to understand how Earth's crust deforms in response to plate tectonics and other processes. The project is focused particularly on understanding vertical motions, which may be related to groundwater withdrawal and snow loading and the migration, extraction, and injection of crustal fluids in addition to faulting and earthquake processes. Detection of anomalous vertical motions in these data will not only improve the quality of earthquake cycle strain rate estimates, but is also a valuable resource for climate, hydrologic, oceanographic, and earthquake engineering communities.The team is focusing on studying vertical deformation using a synthesis of GAGE Facility (Global Positioning System and InSAR) and coastal tide gauge data spanning the Pacific-North American plate boundary. The project is developing well-constrained time-series model products of 3D earthquake cycle deformation using integrated high accuracy GPS point measurements, high spatial resolution InSAR measurements, and long-period tide gauge vertical time series observations. This research project has four main objectives: (1) preparing a contemporary high-resolution GPS-constrained 4D model of vertical and horizontal crustal deformation of the SAFS; (2) using these models to correct inherent errors in InSAR data from new satellites through integrated analysis of GPS and InSAR; (3) construction of a refined 4D time series of crustal deformation derived GPS, InSAR, and tide gauge time-series data; and (4) detecting and understanding non-tectonic deformation common in both InSAR and GPS data. In addition, the team is developing outreach materials describing how InSAR observations are made and used in modeling crustal deformation and distributing those via the Active Earth kiosks supported by NSF, and is releasing software tools to enable geodetic data analyses by the broad Earth science community.